The objective of more complete integration of unmanned vehicles into maritime command and control systems has been set out in previous papers, as has the progress made through the MAPLE (Maritime Autonomous Platform Exploitation) and the demonstrations undertaken at Unmanned Warrior in 2016.  This paper details the significant progress that has subsequently been achieved in the fourth phase of MAPLE, in the run up to a further set of demonstrations in Australia in late 2018.  Using a comprehensive synthetic environment and a process of iterative development, the ACER (Autonomy Control Exploitation & Realisation) demonstrator is being updated to include new functionality that closes gaps in the MAPLE visionary Persistent Architecture (PA).  Specifically this will introduce enhanced Situational Awareness for the operator during Mission Execution, providing details of UxV asset and payload status.  Additional functionality will also provide Payload control.  Summarising these developments and outlining their significance, the paper will give illustrations of potential applications.  Ahead of the Australian Wizard of Aus demonstrations, under the multinational technology co-operation programme (TTCP) and part of Autonomous Warrior, the MAPLE team will further support the STANAG 4586 interface and will undertake derisking work in preparation for the integration of TTCP vehicles provided by Australia, New Zealand and the US. The paper outlines the relevance of this development and how it will be utilised in the Australian demonstration.  Finally, the paper will look forward to the developments planned in both future phase of MAPLE and under QinetiQ’s participation with the multinational EU Ocean 2020 programme.